package ServerPackge;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class StaticResourceUtil {


    /**
     * 获取静态字眼绝对路径
     * @param path
     * @return
     */
    public static String getAbsolutePath(String path){
        String absolutePath = StaticResourceUtil.class.getResource("/").getPath();
        return absolutePath.replaceAll("\\\\","/") + path;
    }

    /**
     * 读取静态资源文件输入流，通过输出流输出
     * @param inputStream
     * @param outputStream
     * @throws IOException
     */
    public static void outputStaticResource(InputStream inputStream, OutputStream outputStream) throws IOException {
        int count = 0;
        while(count == 0){
            count = inputStream.available();
        }

        int resourceSize = count;
        // 输出请求头
        outputStream.write(HttpProtocolUtil.getHttpHeader200(resourceSize).getBytes());

        // 输出内容
        long written = 0; // 已读取字符长度
        int byteSize = 1024; // 每次读取缓存长度

        byte[] bytes = new byte[byteSize];

        while(written < resourceSize){
            if(written + byteSize > resourceSize){// 说明剩余未读取大小不足一个 1024值，使用真实长度处理
                byteSize = (int) (resourceSize - written); // 剩余文件内容长度
                bytes = new byte[byteSize];
            }
            inputStream.read(bytes);
            outputStream.write(bytes);

            outputStream.flush();
            written += byteSize;
        }
    }

}
